Installation of lateral linings with sealing collar from the main pipeline out

ABSTRACT

A liner for a lateral pipe which leads into a main pipe having at one end a collar for installation at the location where the lateral liner meets the main, the collar extending along the interior of the main seating against the opening of the lateral. The liner mounted in a launching device is installed by everting the liner through an opening in the collar by means of fluid under pressure supplied through a pressure pipe in the launching device, the launcher held in position by an inflatable bladder which is inflated by said fluid, and against the collar for sealing the lateral/main pipe junction.

This is a continuation of application Ser. No. 07/934,678, filed Sep.10, 1992, now U.S. Pat. No. 5,393,481.

BACKGROUND OF THE INVENTION

This invention relates to the lining of pipelines or passageways, usingflexible tubular materials which are impregnated with curable syntheticresin and which, when placed in position lining the pipeline orpassageway are held by fluid pressure against the pipeline or passagewaysurface until the resin cures to a hard condition leaving a hard liningpipe lying on the pipeline or passageway surface.

The most widely practised method using such resin impregnated linings isdisclosed in British Patent No. 1449455 from which it will be seen thatthe impregnated lining is applied to the pipeline or passageway surfaceby eversion of same into the pipeline or passageway, using fluidpressure.

The present invention is concerned with lining pipelines which arecalled "laterals" insofar as they enter sidewise a main pipeline orpassageway, such as a main sewer. Of any particular main line, there maybe a plurality of laterals entering the main line, and it frequentlyarises that the laterals have to be lined by means of a resinimpregnated tube. Using existing methods for lining laterals, it is notpossible to perform any lining operation of a second or subsequentlateral whilst the lining in one lateral is being cured. As the curetime may take up to 5 or 6 hours, if a section of main line having say 5laterals to be lined is involved, the minimum total time to line alllaterals will be in the order of 25 to 30 hours. As these liningoperations are required to be carried out during the night for purposesof convenience, it is often the case that the completion of the work hasto take place over several evenings and therefore the work crew mustdepart the site and return at a later date to complete the work.

The present invention is concerned with providing an arrangement whereinthe completion of a plurality of lateral lining operations may beeffected in a much shorter period.

SUMMARY OF THE INVENTION

In accordance with the present invention, a plurality of lateralsmeeting a common main line are lined by inserting resin impregnatedlinings into said laterals and to hold same in position by fluidpressure whilst curing of the resin takes place, and after insertion ofeach lining, a seal arrangement at the location where the lateral meetsthe main line enables the second and subsequent laterals to be linedwhilst the first or previously inserted lining is held in position andis being cured.

The seal arrangement may comprise a flexible bag which is pressurisedwith the medium which urges the lining against the lateral surface so asto prevent escape of the pressurising medium, but such bag allowingpressure fluid supplying pipes to pass to the inside or outside of thebag and to other lateral connections downstream of the bag in the mainpipe whereby such other laterals may be lined by the eversion there intoof a resin impregnated lining tube, the holding of the lining tube tothe lateral surface being affected by fluid pressure, and a sealing bagretaining the lining in position and forming a seal between the lateraland the main line.

It will be seen that by using the method, the linings for the lateralscan be inserted sequentially, and held in installed position underpressure, and cured simultaneously. A plurality of laterals can be linedand cured in a total time equal to the time it takes to line one lateralmultiplied by the number of laterals plus the curing time for one of thelateral linings which total time in the case of 5 laterals may be in theorder of 8 hours, which is a considerable reduction from the 25-30 hourswhich are required for the lining of 5 laterals by the conventionalmethod. For example therefore the lateral lining on any particularcontract may be capable of being completed in one evening as opposed tobeing completed in stages over two or three evenings.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described, by way of example,with reference to the accompanying diagrammatic drawings, wherein:

FIG. 1 is a diagrammatic side elevation showing the method by which alateral is lined in accordance with the method of the invention;

FIG. 2 is a sectional elevation taken on the line II--II;

FIG. 3 is an enlarged sectional view of the detail ringed III in FIG. 1;

FIG. 4 is an enlarged sectional view of the detail ringed IV in FIG. 1;

FIG. 5 is a sectional side view of an alternative form of apparatus forcarrying out the method of the invention.

FIG. 6 is an end view of the arrangement shown in FIG. 5; and

FIG. 7 is a perspective view of the lining tube used in the method ofFIGS. 5 and 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings, in FIG. 1 a main line 10 is intersected by alateral 12 which is to be lined in accordance with a first method of theinvention.

For the lining operation, a resin impregnated flexible lining tube 14has a beaded end 16 which is reinforced, and forms a ring which seatsagainst the opening of the lateral 12. The tube 14 is loaded inside acarrier tube 18. Carrier tube 18 has one end 20 anchored to an elbowpipe 22, and to the other end of the elbow 22 is connected a containmenttube 24. A disc 26 seals the other end of the containment tube, butextending through the disc is a pressure hose 28 and a bleed hose 30.

The pressure hose 28 and bleed hose 30 can slide through the disc 26 asinsertion of the lining tube 14 takes place as will be explained.

If reference is made now to FIG. 4, as shown, the tail end of thecarrier tube 18 is closed around the bleed hose 30, and the pressurehose 28 is connected to the closed end of the carrier tube 18. The endof the lining tube 14 stops short of the end of the carrier tube so thatthe lining tube can be left in position lining the lateral 12.

The method of insertion comprises the introduction of pressurisingfluid, water or gas, through the pressure hose 28 into the space betweenthe containment tube 24 and the carrier tube 18 with the result that thecarrier tube 18 and the lining tube 14 are everted as shown at 32 inFIG. 1 into the lateral 12, the lining tube 14 being presented to thelateral surface. The assembly of tubes 14 and 18 therefore everts intothe lateral 12 and the pressure hose 28 and the bleed hose 30 are pulledthrough the containment tube, through the elbow 22 and up to the top endof the lateral. The portion 30A of the bleed hose projects out of theend of the eversion face so that if any water collects above the lining,it can bleed through end 30A, which is provided with apertures 34 forthis purpose, out of the tube 30 and back to drain so that there will beno undesirable collection of liquid in the lateral whilst lining istaking place.

The pressure fluid which is supplied by the hose 28 leaks through anaperture 36 in the elbow 22 and pressurises a bag or bladder 38surrounding the elbow as shown. The bladder is therefore inflated so asto seal against the main line 10 and to seal the end 16 of the lining.The aperture is provided with or acts as a pressure reduction means sothat whilst the everting pressure may be of the order of 20 p.s.i., thepressure in the bag or bladder 38 is much lower e.g. in the order of 5p.s.i. The bladder 38 remains pressurised as long as the pressure ismaintained inside the everted lining and carrier tube. As soon as thisposition has been reached, a towing assembly 40 which is used forpositioning the elbow 22 by being connected thereto through a link 42fast with elbow 22, is released from that link insofar as, as shown inFIG. 3, the link 42 has a socket 44 in which engages a centralising pin46. The wall of the socket 44 has aligned apertures 48, 50 in which pegs52 and 54 engage, these pegs being carried by pivotable jaws 56 and 58.The jaws 56 and 58 are connected to the clamping device 60 havingswingable arms 62 and 64 on the ends of which are provided guide rollers66 and 68. As the bladder 38 inflates, the rollers 66 which are heldinwardly by spring action are caused to pivot to the position shown inFIG. 1 which has the effect of moving the jaws 56 and 58 apart to removethe pegs 52 and 54 from the apertures 48 and 50 and the positioningdevice 40 and the device 60 with the rollers and jaws can be detachedfrom the bladder and the connecting tube 42 so that it can be pulledalong the line 10 away from the inflated bladder.

A series of additional pressure pipes and corresponding bleed pipes 70,72 (four in all) extend to the outside of the bladder 38 and areremovably attached to the positioning device 40. Device 40 is moved tothe other end of the main line 10 and a second assembly comprising elbow22, bladder 38, containment tube 24, sealing disc 26 and the carriertube and lining 18 and 14 with bladder 38 is connected to thepositioning device (and one of the additional pressure/bleed pipe pair)which is again moved back into the main line 10 until the next lateralto be lined is reached when the device is placed in register therewithso that by appropriate pressurising of the assembly as described inrelation to FIG. 1, the lining tube can be inserted into position in thelateral. When this process has been completed, the procedure is againrepeated so that all five laterals can have lining tubes placed thereinand the lining tubes can be cured simultaneously.

To effect the curing, it may be necessary to circulate hot water, steamor hot air through the pressurising hoses 28, 70 and 72 if the resin isof the heat cure type.

When curing has been completed, it is simply a matter of releasing thepressure in each of the bladders 38 which will then collapse, and eachcan be removed from the main line 10 by pulling on the pressure hose 28,70 or 72 as the case may be. The retraction of such hose retracts thecarrier tube 18 from inside the lateral, leaving the rigid lining tube14 in position.

In the alternative arrangement shown in FIGS. 5, 6 and 7, the method ofoperation is the same as that described in relation to FIGS. 1-4, andonly the structure of the bladder is varied in order to make it easierfor the additonal pressure/bleed pipes to pass the bladder assemblywhilst it is inflated.

Thus, the bladder is in the form of diametrically opposite inflatablepillows 80, 82 which are carried on inner diametrically opposite plates,84, 86 connected to the elbow 22 by being bolted thereto by bolts 88.Plate 86 is carried by the elbow 22 on a radial leg 90 which isadjustable in length so that the arrangement can be adjusted to suitpipes of different diameters. Pillow 80 has a hole, 92 therein throughwhich the elbow pipe 22 passes the pipe 94 which extends from the elbow22 forms passage for the everting medium and also carries the coupling42. Pipes 96, 98 connect the interior of the pipe 94 and the pillows 80,82. The aperture 36 is also shown in FIG. 5. The operation of thearrangement of FIGS. 5, 6 and 7 will be understood from the previousdescription of the embodiment of FIGS. 1-4. The lining 14 and thecarrier tube 18 are inverted by pressurising the interior of elbow 22and at the same time by passage of the pressurising medium through hole36, pipe 94, and pipes 96, 98 inflation of the pillows 80, 82 to sealthe lateral aperture whilst eversion takes place. The additionalpressure/bleed pipes 70, 72 can pass between the pillows easily as shownin FIG. 6 in dotted lines. Whilst pillow 80 seals the lateral, pillow 82forms a reaction means.

The lining tube 14 in the FIG. 7 arrangement as shown has a collar 100which is preferably a sealed envelope containing a resin absorbentmaterial which is impregnated with curable synthetic resin similar tothe tube itself. As the lining tube 14 cures so the collar will alsocure and the collar remains in place around the lateral aperture.

The present invention provides a system whereby a plurality of laterallinings may be cured simultaneously thereby reducing the overall curetime in a contract where a number of laterals have to be lined.

I claim:
 1. A method of lining a lateral pipe leading into a main pipefrom the main pipe out, comprisingproviding a resin impregnated laterallining tube of finite length and open ended having at one end a collarof resin impregnated material with a central opening, the end of thelateral lining bonded to the collar about the opening, the collaradapted to extend into the main pipe and contact the interior surface ofthe main pipe at the location where the lateral meets the main pipe withthe opposite end of the lateral lining extending into the lateral,positioning the collar in the main pipe at the entrance to the lateralwith the opening in the collar aligned with the lateral; inserting thelateral lining into the lateral pipe using a fluid medium under pressureto evert the liner through the opening in the collar, applying pressureto the lateral lining tube, and applying fluid pressure to the collar onthe surface of the main pipe to cure the collar against the main pipeand form a seal at the location where the lateral meets the main pipe ascuring of the resin takes place.
 2. A method according to claim 1,wherein the seal is formed by an inflatable means, said means beinginflated by the fluid medium used for inserting the lateral lining, butat a lower pressure.
 3. A method according to claim 1 wherein the fluidmedium is supplied to insert the lateral lining, by means of a pressurepipe, and at least one additional pressure pipe extends past the sealarrangement so that pressure fluid can be applied to another laterallining remote from the first mentioned lateral whilst curing of thefirst mentioned lateral lining is taking place.
 4. A method to claim 1,wherein the seal arrangement is formed by use of an elbow pipe toposition the lateral lining at the entrance to the lateral and throughwhich the lateral lining is everted to be inserted into the lateral. 5.A method according to claim 2, wherein the inflatable means comprises abag or bladder which is inflated against the main pipe surface.
 6. Amethod according to claim 5, wherein the bag or bladder is in the formof a pair of spaced diametrically opposed inflatable pillows.
 7. Amethod of lining a lateral pipe leading into a main pipe,comprisingproviding a resin impregnated lateral lining tube of finitelength and open ended and having at one end a collar of resinimpregnated material with a central opening, the end of the laterallining bonded to the collar about the opening, the collar adapted toextend into the main pipe and contact the interior surface of the mainpipe at the location where the lateral meets the main pipe with theopposite end of the lateral lining extending into the lateral, insertingthe lateral lining into the lateral pipe and using a fluid medium underpressure expanding the lateral lining against the lateral wall, applyingpressure to the lateral lining tube, and applying fluid pressure to thecollar on the surface of the main pipe to cure the collar against themain pipe and form a seal at the location where the lateral meets themain pipe as curing of the resin takes place.
 8. The method according toclaim 7, including applying pressure to the collar by an inflatablemeans which is a bag or bladder.
 9. The method according to claim 8,including pressing the collar against the main pipe by an inflatablemeans connected to an elbow pipe and inverting the lateral liningthrough the elbow pipe into the lateral.